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This paper deals with a research project concerning an effective utilization of exhaust gas heat. Exhaust gas from a exhaust gas-separate type two-stroke cycle engine containing a high concentration of unburned gas was temporarily stored in a floating-bell type tank as an form of heat energy conservation, while in the previous report [1]* exhaust heat was recovered with continuous operation. A Stirling engine with a hot-water supply system was then used to oxidize or burn again the exhaust gas in a catalyzer and an after-burner unit in order to recover the unspent heat energy from the exhaust gas. A three-way catalyzer was employed to remove pollutants both from the combustion gas in this process and the high-concentration burned gas from the two-stroke cycle engine. The results of the research in the present paper are intended as a follow-up of the previous report [1] to clarify a method for the more effective use of exhaust gas heat.

This paper details the investigation of the properties of inlet gases and shows how they affect the flow patterns immediately in front of the catalyst and the subsequent loss of efficiency. A thorough analysis of the flow distribution at the inlet of the catalyst enabled the effective catalyst diameter to be calculated. Subsequent calculations were then carried out to determine the loss of catalyst function through flow maldistribution. Experimental work involved flowing engine proportioned amounts of air through canisters of a fixed geometric profile containing a catalyst. Inlet cones of angles 10°, 15° and 45° were flowed to estimate the effect of the cone design on the velocity distributions at the face of the catalyst. Simple geometric profiles were investigated to allow a thorough understanding of the mechanism of flow to be comprehended and its affect on catalyst conversion to be analysed.

A 500 cc single cylinder two-stroke engine employing cross scavenging and direct air-assisted gasoline injection is described. Preliminary engine test results are presented for 3000 rpm full load and 1600 rpm part load operating conditions. The effects of fuel injection timing on full and part load brake specific fuel consumption and exhaust emissions are examined.

The Dyna-Bite®* traction system, developed by the Omitrac corporation, consists of a series of retractable spades which can be placed over a conventional tractor drive tires to improve traction under varying soil conditions. An initial model of the traction system was tested in 1986 (1)**. The performance of this model was compared with a 2WD tractor equipped with single drive tires and a front wheel assist (FWA) tractor. More recently, an improved model DB3-RM was evaluated at the University of Saskatchewan. The results were compared with an equally ballasted IH 1086 2WD tractor equipped with single and dual drive wheels (2). Tests for both studies were conducted on a wide range of soil moisture conditions under a variety of drawbar pull levels. Both models of the traction system provided significant traction improvements. Initial model of the traction system performed nearly as good as FWA while the later model proved superior to both single and dual wheels.

A machine was built to study non-rolling tire stiffness and damping coefficient of agricultural tractor tires in the vertical direction. Measurements of static deflection and contact area on a rigid surface can be performed. During dynamic experiments, a sinusoidal deflection function is imposed to the test tire to determine dynamic stiffness and damping coefficient. The experimental setup and methodology are described in this paper. A complete sample test and its analysis are also presented. This paper was approved for publication by the Director of the Louisiana Agricultural Experiment Station as publication number 93-07-7238. Trade names are used solely to provide specific information. Mention of a trade name does not constitute a warranty of the product by the Louisiana Agricultural Experiment Station of the LSU Agricultural Center nor an endorsement to the exclusion of other products not mentioned. The authors are François P. Brassart, Graduate Research Assistant, and Malcolm E.

The emissions produced from a simple carburetted crankcase scavenged two-stroke cycle engine primarily arise due to losses of fresh charge from the exhaust port during the scavenging process. These losses lead to inferior fuel consumption and a negative impact on the environment. Pressure on exhaust emissions and fuel consumption has reduced the number of applications of the two-stroke cycle engine over the years, however the attributes of simplicity, high power density and potential low manufacturing costs have ensured its continuing use for mopeds and motorcycles, small outboard engines and small utility engines. Even these last bastions of the simple two-stroke engine are being challenged by the four stroke alternative as emissions legislation becomes tighter and is newly formulated for many categories of engines. A simple solution is described which reduces short circuit and scavenge losses in a cost effective way.

The dynamic behavior of a towed vibratory roller has been studied through modal testing techniques. Physical mass changes of the frame of the roller have been made to avoid resonance problems and the predicted behavior improvement of the roller is collaborated in the experiments.

Electrochemical Impedance Spectroscopy (EIS) and Thermal Wave Imaging (TWI) are complementary techniques which can be used to detect and estimate Impact Induced Corrosion (IIC) at the metal-polymer interface. This paper describes the use of the above techniques to detect Impact Induced Corrosion in a variety of pre-coated and painted sheet steels. It has been possible to show, that IIC is a threshold phenomenon and depends on the type of galvanized coating. Evaluation of IIC, using a high performance indoor accelerated test and preliminary data from the proving grounds are presented in this paper.

Stone impact damage to automotive paint finishes has drawn significant attention in recent years from both automobile manufacturers and their OEM paint suppliers. This work describes the design and implementation of a precision instrumented impact device to perform a wide range of phenomenological studies of impact processes. A precision launch mechanism, control of the appropriate impact and environmental variables, a versatile sample holder, and optional advanced instrumentation render this device useful both as a quality control bench marking tool and as an instrument to design improved impact resistant coating systems.

A universal autonomous controlled heat transferring module on base of two-phase loop with capillary pump have been elaborated. This module consists of one evapourator and one radiator-condenser. Various variants for suggested module control by using of active or passive elements, providing the CPL start-up, restarting and temperature regulation, have been considered. There is determined a structure concept and recommendations on mathematical modeling of Thermal Control System (TCS), made on base of several controlled heat transferring modules with capillary pumps, are given. There are given results of computer experiment with mathematical model of artificial Earth satellite payload TCS. This TCS consists of four controlled, independent in power supply, CPL, which start-up and control are carried out by using of passive devices.

The approarch to utilization of software HEAT'90 to thermal simulation of heat pipes and units of their connections with elements of thermal control systems is presented. The application of finite elements method for solution of problems, interective regime of functioning “software-user” allow to simulate enough complicated 2-D constructions and transfer processes by user without special programme languaege knowledge and trainig. The examples of software employment are discussed like next: efficiecy of flange unit in heat pipe input/output zones; influence of dried grooves presence on temperature field in cross-section; distribution along pipe length; efficiency of unit “heat pipe-honeycomb radiator” and other. The main development of software for elements of thermal control systems design application are shown.

A capillary pumped two-phase ammonia heat transport loop, developed at Lavochkin Assoc., Moscow, was tested under laboratory conditions at ERNO, Bremen. The tubular capillary pump evaporator contains a sintered Nickel powder body with a small pore size of 1. 5 μm. The line diameter of the vapour and the liquid line is only 6 mm and 4 mm, respectively, allowing an easy accomodation to any architecture in the filled state. The objective of the test was to determine the heat transport performance of the loop under different orientations w.r.t. gravity under steady state and transient, in particular priming load conditions. The tests have demonstrated a large heat transport performance of more than 1100 W in a vertical orientation, where the evaporator was located 2 m (!) above the condenser. The priming ability appears to depend on the load timeline as well as on the orientation.

The results of experimental and analytical investigation of startup regimes of CPLs are presented. The experimental data upon change of temperatures and pressures in the loop during the startup process in the loop are adduced. The model of a startup is formulated and the analysis of conditions realizing reliable startup is fulfilled.

In the frame of an ESA technology program, the development of a High Capacity Grooved Heat Pipe (HGP), based on the thermal requirements of the next generation of telecommunication satellites, was contracted to SABCA. Different promising concepts and methods of groove technology were reviewed. A trade-off and design study was performed on potential HGP concepts, taking into account theoretical performances (on earth and in micro-gravity), ease of manufacturing and of assembly as well as the heat pipe working reliability and priming capability. The two finally selected concepts were aluminium extruded heat pipes (outer diameter of 25 mm, vapour core diameter of 15 mm), based on a multi re-entrant grooves concept or on a mixed rectangular/re-entrant grooves concept.

The use of carbon fiber reinforced composite materials in unit-carrying satellite radiator panels was studied. Different panel architectures and component materials were identified. The mass-specific heat rejection capability of the most promising of these configurations was analytically determined for different heat loads having either the stiffness or the strength of a reference configuration. The analytical results clearly define the optimum panel configuration under the different structural and thermal requirements. The panel configuration consisting of carbon fiber reinforced plastic (CFRP) facesheets, aluminium honeycomb core and top-mounted aluminium heatpipes was found to be superior in a wide range of requirements and therefore selected as a reference concept. A flexible adhesive was used as the thermal interface between both components having significantly different thermal expansion coefficients.

Automotive technologies such as fuel injection, anti-lock braking systems and automatically adjusting suspension systems have created a need for soft magnetic alloys having good corrosion resistance and fabrication characteristics, but with higher saturation flux density (Bs) and more consistent magnetic performance than ferritic stainless steels. This paper will describe the development of a family of controlled chemistry Chrome Core™ * alloys specifically designed for use in magnetic components where corrosion resistance substantially superior to that of pure iron, low carbon steel and silicon-iron alloys is required without the substantial decrease in saturation flux density and inconsistent magnetic response associated with conventional ferritic stainless steel.

Alternative materials to the present terne (hot-dip lead-tin) coated steel are required for fuel tank compatibility with future flexible fuel blends of methanol and gasoline. In addition, the alternative materials must be more resistant to external corrosion from road salts than the present terne coated steel. The goal of the study described in this paper was to identify a coated steel that will satisfy these requirements. Materials evaluated included organic coatings over terne, galvanneal, and zinc-nickel coated sheet steels. The fuel resistance of these materials was evaluated by exposure to various flex fuel blends at elevated temperature. The external corrosion performance of these coatings was examined by exposure to salt spray and cyclic corrosion laboratory tests. The results of these tests are described in terms of resistance to paint delamination, red rust formation at scribes, cut edges, and deformed areas.

Cosmetic corrosion of painted automotive substrates is a complex phenomenon being a function of number of environmental variables and material properties. To address the need for reliable accelerated corrosion tests, a high performance corrosion chamber was built by VOLVO car corporation, Gothenberg, Sweden. Using a statistically designed program of experiments, excellent correlation between outdoor and laboratory simulations have been established using the VOLVO technique. Traditional methods for corrosion data analysis has been based on the use of well known statistical methods. In this paper, we have introduced Artificial Neural Networks (ANN) to study and establish complex relations between scribe creep data and the variables that govern cosmetic corrosion performance. Application of the ANN methodology as a predictive tool has been discussed.

Cosmetic corrosion resistance of coated and cold rolled steel sheet products is being determined by use of test coupons (paint panels) mounted on full-size pickup trucks operating in the severe corrosive environments of Montreal, Quebec and St. John's, Newfoundland, Canada, Ten standard materials from the joint AISI/SAE corrosion test development program, including hot-dip galvanized, galvannealed, electroplated zinc and zinc-nickel alloy-coated, as well as phosphated and unphosphated cold rolled steel have been under evaluation for five years. The results of these evaluations are described in terms of resistance to paint undercutting (creepback) and red rust staining at scratches (scribes) through the paint film to the steel substrate. The effects of horizontal and vertical test coupon orientations are considered. Performance of the materials in this evaluation provides an excellent standard of real-world behavior against which the reliability of accelerated tests can be determined.

During the last decade many materials were developed to improve corrosion resistance of automotive vehicles as to cosmetic and perforation corrosion. Tests were carried out based upon classic laboratory salt spray testing as well as on newly developed cyclic laboratory tests and on vehicle tests. To translate the laboratory test results into practice it is necessary to understand the corrosion mechanisms occuring in laboratory experiments compared to the corrosion mechanisms in real practice. This paper deals with the understanding of laboratory corrosion mechanisms in cyclic corrosion testing compared to some static outdoor corrosion tests. It is shown that delamination rate of scribed panels of painted hot dip galvanized, and galvannealed materials is highly controlled by the speed of anodic dissolution of the “zinc” due to the electrical characteristics of the corrosion products formed in the scribe and under the paint layer. These characteristics depend on the type of test.